X intercept is (1,0)
y intercept is (0,-4)
You would do 21 divided by 3 and get 7.
The answer is 7 kids are in the line.
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Answer:

Step-by-step explanation:

Hope this helps.
5 .This is called the greatest common factor.
You can list all the factors(ways to divide) of each number and find the biggest one.
15'1,3,5,15
10'1,2,5,10
The greatest they share is 5